Tully says to beware of "bubble" real estate markets, where the price of a house completely diverges from the fundamentals that determine the value of a home personal income and rental rates in a particular market.

NPR: Avoiding the Housing Market 'Dead Zone'

Income from the rental of personal property if you were not in the business of renting property.

FORBES: Taxes From A To Z (2013): M Is For Miscellaneous Income

Expenses associated with a rental property must be allocated between rental and personal use, and any allocable rental expenses are allowed in full to offset any rental income.

FORBES: Tax Lesson Of The Day: No Good Can Come From Letting Your In-Laws Mooch Off Of You